Adamo P, Arienzo M, Bianco M R, Terribile F, Violante P
Dipartimento di Scienze del Suolo, della Pianta e dell'Ambiente, Università di Napoli Federico II, Portici, Italy.
Sci Total Environ. 2002 Aug 5;295(1-3):17-34. doi: 10.1016/s0048-9697(02)00020-7.
The total contents and the chemical and mineralogical forms of the metals Fe, Al, Cu, Co, Cr, Pb, Zn, Ni and Mn in the horizons of a soil profile, representative of an area devoted to stocking raw materials in the dismantled iron-steel industrial plant of ILVA of Bagnoli (Naples), were studied by physical and chemical methods. The geological setting of the study area is the result of volcanic activity in the Phlegrean Fields, a group of polygenic volcanoes to the west of Naples, which give rise to the parent soil material. Soil morphology appeared to be strongly disturbed by the occurrence and stratification of materials used in the industrial process. Fine sediments illuviation down the profile resulted in the occurrence of silt and clay coatings. The total contents of Cu, Co, Cr, Pb, Zn and Ni, in the whole soil samples, especially in the surface layers, were above the regulatory levels (Cu 120, Co 20, Cr 150, Pb 100, Zn 150, Ni 120 mg kg(-1)) stated by the Italian Ministry of Environment for soils in public, private and residential areas, and below the levels (Cu 600, Co 250, Cr 800, Pb 1000, Zn 1500, Ni 500 mg kg(-1)) outlined for soils and subsoils of industrial and commercial areas (Gazzetta Ufficiale della Repubblica Italiana, 1999). Speciation of heavy metals and the determination of the different chemical pools in the fraction < 2 mm identified the large presence of elements trapped in the mineralogical structure of oxides and silicates and occluded in easily reducible manganese or iron oxides. A constant amount of Cu was associated with organic compounds. A significant amount of Zn (> 20%) was extracted in diluted acetic acid solution, indicating that the element was present in a more readily and potentially available form. In the clay fraction (< 2 microm) heavy metals were associated with both amorphous and crystalline iron forms. The presence of iron-rich clay coatings was evident in the illuvial pores of deeper horizons. Enrichment in Cu, Co, Cr and Zn of the coatings was observed. Possible translocation of metals down through the soil profile mainly bound to fine particles of relatively inert forms of iron is hypothesised. The dispersion in water of the clay fraction resulted in an average percentage dispersion of approximately 20% with a peak of 41.7% at 68-72 cm depth. Magnetite, goethite, hematite, calcite and quartz mixed with K-feldspars, clynopyroxenes and mica occurred in the coarse sand fractions (2-0.2 mm) of the soil samples from all the surface horizons. Talcum and goethite together with clay minerals at 1.4 nm, kaolinite and illite were found in the clays (< 2 microm).
采用物理和化学方法，对代表那不勒斯巴尼奥利伊尔瓦钢铁厂拆解后用于储存原材料区域的土壤剖面各层中金属铁、铝、铜、钴、铬、铅、锌、镍和锰的总量及其化学和矿物形态进行了研究。研究区域的地质背景是弗莱格雷火山群火山活动的结果，该火山群位于那不勒斯以西，是一群多成因火山，形成了母质土壤。土壤形态似乎受到工业过程中使用的材料的出现和分层的强烈干扰。细粒沉积物沿剖面淋溶，导致出现粉砂和粘粒涂层。在整个土壤样品中，尤其是表层，铜、钴、铬、铅、锌和镍的总量高于意大利环境部规定的公共、私人和住宅区土壤的监管水平（铜120、钴20、铬150、铅100、锌150、镍120毫克/千克），低于工业和商业区土壤及底土规定的水平（铜600、钴250、铬800、铅1000、锌1500、镍500毫克/千克）（《意大利共和国官方公报》，1999年）。对小于2毫米部分的重金属形态分析以及不同化学库的测定表明，大量元素被困在氧化物和硅酸盐的矿物结构中，并被包裹在易还原的锰或铁氧化物中。一定量的铜与有机化合物结合。大量的锌（>20%）在稀醋酸溶液中被提取出来，表明该元素以更易获得且潜在可利用的形式存在。在粘粒部分（<2微米），重金属与无定形和结晶态的铁形态相关。在较深层的淀积孔隙中，富含铁的粘粒涂层明显可见。观察到涂层中铜、钴、铬和锌的富集。推测金属可能主要以相对惰性的铁形态细颗粒为载体沿土壤剖面向下迁移。粘粒部分在水中的分散导致平均分散百分比约为20%，在68 - 72厘米深度处达到峰值41.7%。在所有表层土壤样品的粗砂部分（2 - 0.2毫米）中，发现磁铁矿、针铁矿、赤铁矿、方解石和石英与钾长石、单斜辉石和云母混合存在。在粘粒（<2微米）中发现滑石、针铁矿以及1.4纳米的粘土矿物、高岭石和伊利石。
